Related papers: Quarks at the modular $S_4$ cusp
I discuss two topics: i) the empirical adequacy of the Standard Model in the Flavour Sector in view of recent data; ii) the possible existence of a hidden structure in the quark masses and mixings based on textures.
An interesting mass relation between down type quarks and charged leptons has been recently predicted within a supersymmetric SU(3)_c \times SU(2)_L \times U(1)_Y model based on the A4 flavor symmetry. Here we propose a simple extension…
The recent analysis of the electroweak data at CDF indicates that the constraint on the top quark mass is $m_t=174\pm 17 $GeV. We accommodate this result in a new scheme of quark mass matrices in which two elements along the the leading…
Four simple but realistic patterns of quark mass matrices are derived from orbifold models of superstring theory in the absence of gauge symmetries. Two of them correspond to the Ramond-Roberts-Ross types, which have five texture zeros in…
We rewrite the Yukawa interactions of the standard model in terms of flavour-dependent vacuum structure to address the family mass hierarchy and CP violation in both the quark sector and lepton sector. It is realized for the first time that…
We show that the quark flavour structure and CP violating phenomena are strongly correlated in supersymmetric theories. For a generic pattern of supersymmetry breaking the two broad categories of Yukawa couplings, democratic and…
We build a supersymmetric model of quark and lepton masses based on the discrete flavour symmetry group T', the double covering of A_4. In the lepton sector our model is practically indistinguishable from recent models based on A_4 and, in…
The premise of an organizing quadratic hierarchy rule in lepton-quark flavor physics was used earlier for explanation of the hierarchy patterns of four generic pairs of flavor quantities 1) charged-lepton and 2) neutrino deviations from…
We construct a model for the quark mass and flavor mixing matrices, based on the hypothesis that the flavor weak eigenstates in the three families are distinguished by a spontaneously broken discrete $Z_6$ chiral symmetry. In a leading…
We study a flavor model with $A_4$ symmetry which originates from $S_4$ modular group. In $S_4$ symmetry, $Z_2$ subgroup can be anomalous, and then $S_4$ can be violated to $A_4$. Starting with a $S_4$ symmetric Lagrangian at the tree…
One of the major challenges of particle physics has been to gain an in-depth understanding of the role of quark flavor and measurements and theoretical interpretations of their results have advanced tremendously: apart from masses and…
In this paper, we investigate lepton mass spectra, flavor mixing and CP violation with a modular $S^{}_4$ symmetry under the assumption that neutrinos are Dirac fermions. We find that the Majorana mass term can be forbidden by adjusting the…
We present a model for quark masses and mixing, featuring geometrical CP violation through a \Delta(27) triplet. By employing a single U(1)_F or Z_N symmetry in addition to \Delta(27), we forbid all terms in the scalar potential that would…
We study quark and lepton masses and mixings in a double covering of modular $A_4$ flavor symmetry in which we search for common solution of a single modulus $\tau$, applying chi-square numerical analysis under the as minimum framework as…
Pursuing a bottom-up approach to explore which flavor symmetry could serve as an explanation of the observed fermion masses and mixings, we discuss an extension of the standard model (SM) where the flavor structure for both quarks and…
Measurements of CP asymmetries in B decays will soon be made at $B$ factories and hadron machines. In light of this, we review and update the profile of the CKM unitarity triangle and the resulting CP asymmetries in B decays. This is done…
We present minimalist constructions for lepton masses and mixing based on flavour symmetry under the modular group $\Gamma_N$ of lowest level $N=2$. As opposed to the only existing model of $\Gamma_2\cong S_3$ formulated in a SUSY…
We show that new physics which breaks the left-handed SU(3)_Q quark flavor symmetry induces contributions to CP violation in Delta F = 1 couplings which are approximately universal, in that they are not affected by flavor rotations between…
We propose a model of quark flavor based on an additional $SU(2)\times U(1)$ local symmetry in a warped extra dimensional bulk. In contrast to other works, we break the additional gauge symmetry in the bulk via two complex scalars which…
I explore the rich phase diagram of two-flavor QCD as a function of the quark masses. The theory involves three parameters, including one that is CP violating. As the masses vary, regions of both first and second order transitions are…